update reveal.js

css/reveal.css

@@ -3,7 +3,7 @@
  * http://revealjs.com
  * MIT licensed
  *
- * Copyright (C) 2019 Hakim El Hattab, http://hakim.se
+ * Copyright (C) 2020 Hakim El Hattab, http://hakim.se
  */
 /*********************************************
  * GLOBAL STYLES
@@ -77,29 +77,29 @@ body {
     text-decoration: line-through; }
 
 .reveal .slides section .fragment.fade-up {
-  -webkit-transform: translate(0, 20%);
-          transform: translate(0, 20%); }
+  -webkit-transform: translate(0, 40px);
+          transform: translate(0, 40px); }
   .reveal .slides section .fragment.fade-up.visible {
     -webkit-transform: translate(0, 0);
             transform: translate(0, 0); }
 
 .reveal .slides section .fragment.fade-down {
-  -webkit-transform: translate(0, -20%);
-          transform: translate(0, -20%); }
+  -webkit-transform: translate(0, -40px);
+          transform: translate(0, -40px); }
   .reveal .slides section .fragment.fade-down.visible {
     -webkit-transform: translate(0, 0);
             transform: translate(0, 0); }
 
 .reveal .slides section .fragment.fade-right {
-  -webkit-transform: translate(-20%, 0);
-          transform: translate(-20%, 0); }
+  -webkit-transform: translate(-40px, 0);
+          transform: translate(-40px, 0); }
   .reveal .slides section .fragment.fade-right.visible {
     -webkit-transform: translate(0, 0);
             transform: translate(0, 0); }
 
 .reveal .slides section .fragment.fade-left {
-  -webkit-transform: translate(20%, 0);
-          transform: translate(20%, 0); }
+  -webkit-transform: translate(40px, 0);
+          transform: translate(40px, 0); }
   .reveal .slides section .fragment.fade-left.visible {
     -webkit-transform: translate(0, 0);
             transform: translate(0, 0); }

css/reveal.scss

@@ -3,7 +3,7 @@
  * http://revealjs.com
  * MIT licensed
  *
- * Copyright (C) 2019 Hakim El Hattab, http://hakim.se
+ * Copyright (C) 2020 Hakim El Hattab, http://hakim.se
  */
 
 
@@ -102,7 +102,7 @@ body {
 }
 
 .reveal .slides section .fragment.fade-up {
-	transform: translate(0, 20%);
+	transform: translate(0, 40px);
 
 	&.visible {
 		transform: translate(0, 0);
@@ -110,7 +110,7 @@ body {
 }
 
 .reveal .slides section .fragment.fade-down {
-	transform: translate(0, -20%);
+	transform: translate(0, -40px);
 
 	&.visible {
 		transform: translate(0, 0);
@@ -118,7 +118,7 @@ body {
 }
 
 .reveal .slides section .fragment.fade-right {
-	transform: translate(-20%, 0);
+	transform: translate(-40px, 0);
 
 	&.visible {
 		transform: translate(0, 0);
@@ -126,7 +126,7 @@ body {
 }
 
 .reveal .slides section .fragment.fade-left {
-	transform: translate(20%, 0);
+	transform: translate(40px, 0);
 
 	&.visible {
 		transform: translate(0, 0);

css/theme/README.md

@@ -4,7 +4,7 @@ Themes are written using Sass to keep things modular and reduce the need for rep
 
 ## Creating a Theme
 
-To create your own theme, start by duplicating a ```.scss``` file in [/css/theme/source](https://github.com/hakimel/reveal.js/blob/master/css/theme/source). It will be automatically compiled by Grunt from Sass to CSS (see the [Gruntfile](https://github.com/hakimel/reveal.js/blob/master/Gruntfile.js)) when you run `npm run build -- css-themes`.
+To create your own theme, start by duplicating a ```.scss``` file in [/css/theme/source](https://github.com/hakimel/reveal.js/blob/master/css/theme/source). It will be automatically compiled by Grunt from Sass to CSS (see the [Gruntfile](https://github.com/hakimel/reveal.js/blob/master/gruntfile.js)) when you run `npm run build -- css-themes`.
 
 Each theme file does four things in the following order:
 

js/reveal.js

@@ -3,7 +3,7 @@
  * http://revealjs.com
  * MIT licensed
  *
- * Copyright (C) 2019 Hakim El Hattab, http://hakim.se
+ * Copyright (C) 2020 Hakim El Hattab, http://hakim.se
  */
 (function( root, factory ) {
 	if( typeof define === 'function' && define.amd ) {
@@ -26,14 +26,18 @@
 	var Reveal;
 
 	// The reveal.js version
-	var VERSION = '3.8.0';
+	var VERSION = '3.9.1';
 
 	var SLIDES_SELECTOR = '.slides section',
 		HORIZONTAL_SLIDES_SELECTOR = '.slides>section',
 		VERTICAL_SLIDES_SELECTOR = '.slides>section.present>section',
 		HOME_SLIDE_SELECTOR = '.slides>section:first-of-type',
+
 		UA = navigator.userAgent,
 
+		// Methods that may not be invoked via the postMessage API
+		POST_MESSAGE_METHOD_BLACKLIST = /registerPlugin|registerKeyboardShortcut|addKeyBinding|addEventListener/,
+
 		// Configuration defaults, can be overridden at initialization time
 		config = {
 
@@ -77,9 +81,9 @@
 			// - "c/t":	  Flattened slide number / total slides
 			//
 			// Alternatively, you can provide a function that returns the slide
-			// number for the current slide. The function needs to return an array
-			// with one string [slideNumber] or three strings [n1,delimiter,n2].
-			// See #formatSlideNumber().
+			// number for the current slide. The function should take in a slide
+			// object and return an array with one string [slideNumber] or
+			// three strings [n1,delimiter,n2]. See #formatSlideNumber().
 			slideNumber: false,
 
 			// Can be used to limit the contexts in which the slide number appears
@@ -270,6 +274,11 @@
 			// Number of slides away from the current that are visible
 			viewDistance: 3,
 
+			// Number of slides away from the current that are visible on mobile
+			// devices. It is advisable to set this to a lower number than
+			// viewDistance in order to save resources.
+			mobileViewDistance: 2,
+
 			// The display mode that will be used to show slides
 			display: 'block',
 
@@ -447,7 +456,8 @@
 	 */
 	function checkCapabilities() {
 
-		isMobileDevice = /(iphone|ipod|ipad|android)/gi.test( UA );
+		isMobileDevice = /(iphone|ipod|ipad|android)/gi.test( UA ) ||
+							( navigator.platform === 'MacIntel' && navigator.maxTouchPoints > 1 ); // iPadOS
 		isChrome = /chrome/i.test( UA ) && !/edge/i.test( UA );
 
 		var testElement = document.createElement( 'div' );
@@ -849,17 +859,10 @@
 		// Make sure stretch elements fit on slide
 		layoutSlideContents( slideWidth, slideHeight );
 
-		// Add each slide's index as attributes on itself, we need these
-		// indices to generate slide numbers below
-		toArray( dom.wrapper.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR ) ).forEach( function( hslide, h ) {
-			hslide.setAttribute( 'data-index-h', h );
-
-			if( hslide.classList.contains( 'stack' ) ) {
-				toArray( hslide.querySelectorAll( 'section' ) ).forEach( function( vslide, v ) {
-					vslide.setAttribute( 'data-index-h', h );
-					vslide.setAttribute( 'data-index-v', v );
-				} );
-			}
+		// Compute slide numbers now, before we start duplicating slides
+		var doingSlideNumbers = config.slideNumber && /all|print/i.test( config.showSlideNumber );
+		toArray( dom.wrapper.querySelectorAll( SLIDES_SELECTOR ) ).forEach( function( slide ) {
+			slide.setAttribute( 'data-slide-number', getSlideNumber( slide ) );
 		} );
 
 		// Slide and slide background layout
@@ -930,14 +933,11 @@
 				}
 
 				// Inject slide numbers if `slideNumbers` are enabled
-				if( config.slideNumber && /all|print/i.test( config.showSlideNumber ) ) {
-					var slideNumberH = parseInt( slide.getAttribute( 'data-index-h' ), 10 ) + 1,
-						slideNumberV = parseInt( slide.getAttribute( 'data-index-v' ), 10 ) + 1;
-
+				if( doingSlideNumbers ) {
 					var numberElement = document.createElement( 'div' );
 					numberElement.classList.add( 'slide-number' );
 					numberElement.classList.add( 'slide-number-pdf' );
-					numberElement.innerHTML = formatSlideNumber( slideNumberH, '.', slideNumberV );
+					numberElement.innerHTML = slide.getAttribute( 'data-slide-number' );
 					page.appendChild( numberElement );
 				}
 
@@ -1278,11 +1278,20 @@
 
 					// Check if the requested method can be found
 					if( data.method && typeof Reveal[data.method] === 'function' ) {
+
+						if( POST_MESSAGE_METHOD_BLACKLIST.test( data.method ) === false ) {
+
 							var result = Reveal[data.method].apply( Reveal, data.args );
 
 							// Dispatch a postMessage event with the returned value from
 							// our method invocation for getter functions
 							dispatchPostMessage( 'callback', { method: data.method, result: result } );
+
+						}
+						else {
+							console.warn( 'reveal.js: "'+ data.method +'" is is blacklisted from the postMessage API' );
+						}
+
 					}
 				}
 			}, false );
@@ -2651,34 +2660,37 @@
 	}
 
 	/**
-	 * Return a hash URL that will resolve to the current slide location.
+	 * Return a hash URL that will resolve to the given slide location.
+	 *
+	 * @param {HTMLElement} [slide=currentSlide] The slide to link to
 	 */
-	function locationHash() {
+	function locationHash( slide ) {
 
 		var url = '/';
 
 		// Attempt to create a named link based on the slide's ID
-		var id = currentSlide ? currentSlide.getAttribute( 'id' ) : null;
+		var s = slide || currentSlide;
+		var id = s ? s.getAttribute( 'id' ) : null;
 		if( id ) {
 			id = encodeURIComponent( id );
 		}
 
-		var indexf;
-		if( config.fragmentInURL ) {
-			indexf = getIndices().f;
+		var index = getIndices( slide );
+		if( !config.fragmentInURL ) {
+			index.f = undefined;
 		}
 
 		// If the current slide has an ID, use that as a named link,
 		// but we don't support named links with a fragment index
-		if( typeof id === 'string' && id.length && indexf === undefined ) {
+		if( typeof id === 'string' && id.length && index.f === undefined ) {
 			url = '/' + id;
 		}
 		// Otherwise use the /h/v index
 		else {
 			var hashIndexBase = config.hashOneBasedIndex ? 1 : 0;
-			if( indexh > 0 || indexv > 0 || indexf !== undefined ) url += indexh + hashIndexBase;
-			if( indexv > 0 || indexf !== undefined ) url += '/' + (indexv + hashIndexBase );
-			if( indexf !== undefined ) url += '/' + indexf;
+			if( index.h > 0 || index.v > 0 || index.f !== undefined ) url += index.h + hashIndexBase;
+			if( index.v > 0 || index.f !== undefined ) url += '/' + (index.v + hashIndexBase );
+			if( index.f !== undefined ) url += '/' + index.f;
 		}
 
 		return url;
@@ -3283,9 +3295,10 @@
 			// be visible
 			var viewDistance = isOverview() ? 10 : config.viewDistance;
 
-			// Limit view distance on weaker devices
+			// Shorten the view distance on devices that typically have
+			// less resources
 			if( isMobileDevice ) {
-				viewDistance = isOverview() ? 6 : 2;
+				viewDistance = isOverview() ? 6 : config.mobileViewDistance;
 			}
 
 			// All slides need to be visible when exporting to PDF
@@ -3421,14 +3434,26 @@
 
 		// Update slide number if enabled
 		if( config.slideNumber && dom.slideNumber ) {
+			dom.slideNumber.innerHTML = getSlideNumber();
+		}
+
+	}
+
+	/**
+	 * Returns the HTML string corresponding to the current slide number,
+	 * including formatting.
+	 */
+	function getSlideNumber( slide ) {
 
 		var value;
 		var format = 'h.v';
+		if( slide === undefined ) {
+			slide = currentSlide;
+		}
 
 		if ( typeof config.slideNumber === 'function' ) {
-				value = config.slideNumber();
-			}
-			else {
+			value = config.slideNumber( slide );
+		} else {
 			// Check if a custom number format is available
 			if( typeof config.slideNumber === 'string' ) {
 				format = config.slideNumber;
@@ -3443,23 +3468,21 @@
 			value = [];
 			switch( format ) {
 				case 'c':
-						value.push( getSlidePastCount() + 1 );
+					value.push( getSlidePastCount( slide ) + 1 );
 					break;
 				case 'c/t':
-						value.push( getSlidePastCount() + 1, '/', getTotalSlides() );
-						break;
-					case 'h/v':
-						value.push( indexh + 1 );
-						if( isVerticalSlide() ) value.push( '/', indexv + 1 );
+					value.push( getSlidePastCount( slide ) + 1, '/', getTotalSlides() );
 					break;
 				default:
-						value.push( indexh + 1 );
-						if( isVerticalSlide() ) value.push( '.', indexv + 1 );
+					var indices = getIndices( slide );
+					value.push( indices.h + 1 );
+					var sep = format === 'h/v' ? '/' : '.';
+					if( isVerticalSlide( slide ) ) value.push( sep, indices.v + 1 );
 			}
 		}
 
-			dom.slideNumber.innerHTML = formatSlideNumber( value[0], value[1], value[2] );
-		}
+		var url = '#' + locationHash( slide );
+		return formatSlideNumber( value[0], value[1], value[2], url );
 
 	}
 
@@ -3470,11 +3493,14 @@
 	 * @param {number} a Current slide
 	 * @param {string} delimiter Character to separate slide numbers
 	 * @param {(number|*)} b Total slides
+	 * @param {HTMLElement} [url='#'+locationHash()] The url to link to
 	 * @return {string} HTML string fragment
 	 */
-	function formatSlideNumber( a, delimiter, b ) {
+	function formatSlideNumber( a, delimiter, b, url ) {
 
-		var url = '#' + locationHash();
+		if( url === undefined ) {
+			url = '#' + locationHash();
+		}
 		if( typeof b === 'number' && !isNaN( b ) ) {
 			return  '<a href="' + url + '">' +
 					'<span class="slide-number-a">'+ a +'</span>' +
@@ -3855,6 +3881,7 @@
 					iframe.setAttribute( 'allowfullscreen', '' );
 					iframe.setAttribute( 'mozallowfullscreen', '' );
 					iframe.setAttribute( 'webkitallowfullscreen', '' );
+					iframe.setAttribute( 'allow', 'autoplay' );
 
 					iframe.setAttribute( 'data-src', backgroundIframe );
 
@@ -4224,9 +4251,15 @@
 	 * Returns the number of past slides. This can be used as a global
 	 * flattened index for slides.
 	 *
+	 * @param {HTMLElement} [slide=currentSlide] The slide we're counting before
+	 *
 	 * @return {number} Past slide count
 	 */
-	function getSlidePastCount() {
+	function getSlidePastCount( slide ) {
+
+		if( slide === undefined ) {
+			slide = currentSlide;
+		}
 
 		var horizontalSlides = toArray( dom.wrapper.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR ) );
 
@@ -4242,7 +4275,7 @@
 			for( var j = 0; j < verticalSlides.length; j++ ) {
 
 				// Stop as soon as we arrive at the present
-				if( verticalSlides[j].classList.contains( 'present' ) ) {
+				if( verticalSlides[j] === slide ) {
 					break mainLoop;
 				}
 
@@ -4251,7 +4284,7 @@
 			}
 
 			// Stop as soon as we arrive at the present
-			if( horizontalSlide.classList.contains( 'present' ) ) {
+			if( horizontalSlide === slide ) {
 				break;
 			}
 
@@ -4743,6 +4776,8 @@
 
 			if( fragments.length ) {
 
+				var maxIndex = 0;
+
 				if( typeof index !== 'number' ) {
 					var currentFragment = sortFragments( currentSlide.querySelectorAll( '.fragment.visible' ) ).pop();
 					if( currentFragment ) {
@@ -4756,6 +4791,8 @@
 						i = parseInt( el.getAttribute( 'data-fragment-index' ), 10 );
 					}
 
+					maxIndex = Math.max( maxIndex, i );
+
 					// Visible fragments
 					if( i <= index ) {
 						if( !el.classList.contains( 'visible' ) ) changedFragments.shown.push( el );
@@ -4779,6 +4816,13 @@
 
 				} );
 
+				// Write the current fragment index to the slide <section>.
+				// This can be used by end users to apply styles based on
+				// the current fragment index.
+				index = typeof index === 'number' ? index : -1;
+				index = Math.max( Math.min( index, maxIndex ), -1 );
+				currentSlide.setAttribute( 'data-fragment', index );
+
 			}
 
 		}
@@ -5436,20 +5480,50 @@
 
 				if( deltaX > touch.threshold && Math.abs( deltaX ) > Math.abs( deltaY ) ) {
 					touch.captured = true;
+					if( config.navigationMode === 'linear' ) {
+						if( config.rtl ) {
+							navigateNext();
+						}
+						else {
+							navigatePrev();
+						}
+					}
+					else {
 						navigateLeft();
 					}
+				}
 				else if( deltaX < -touch.threshold && Math.abs( deltaX ) > Math.abs( deltaY ) ) {
 					touch.captured = true;
+					if( config.navigationMode === 'linear' ) {
+						if( config.rtl ) {
+							navigatePrev();
+						}
+						else {
+							navigateNext();
+						}
+					}
+					else {
 						navigateRight();
 					}
+				}
 				else if( deltaY > touch.threshold ) {
 					touch.captured = true;
+					if( config.navigationMode === 'linear' ) {
+						navigatePrev();
+					}
+					else {
 						navigateUp();
 					}
+				}
 				else if( deltaY < -touch.threshold ) {
 					touch.captured = true;
+					if( config.navigationMode === 'linear' ) {
+						navigateNext();
+					}
+					else {
 						navigateDown();
 					}
+				}
 
 				// If we're embedded, only block touch events if they have
 				// triggered an action